An online lifestyle intervention program aimed at improving diet, exercise and other modifiable risk factors for dementia has resulted in better cognition in older adults, Australian research has found.  

The Maintain Your Brain study, which tracked more than 6,000 people aged 55 to 77 across New South Wales for three years, is the largest internet-based trial ever conducted to attempt to prevent cognitive decline.

Half the study participants received online coaching and support in the areas of physical activity, nutrition, brain training and mental health, while the other half received publicly available information.

“We know that 45 per cent of the risk for dementia can be explained by modifiable lifestyle factors, and they include things like physical inactivity, a diet that’s not healthy, being less cognitively active, and depression and anxiety,” Henry Brodaty, study author and leading dementia researcher, said.

Over the course of the study, which was published today in Nature Medicine, participants’ cognition was measured through a series of online tests that assessed memory, reasoning and information processing speed.

“At the end of year three, we found both groups [of participants] improved. The group who had the coaching improved more,” Professor Brodaty, who is also co-director of the Centre for Healthy Brain Ageing (CHeBA) at UNSW, said.

While the overall improvement in cognition was “small”, he said, it was “highly significant” at a population level — equivalent to delaying the onset of dementia by one year, the researchers estimate.

“We know people who have better cognition have got some buffer against dementia,” Professor Brodaty said.

“So they may have the same amount of pathology in the brain … but they’re able to compensate for longer because of what we call ‘cognitive reserve’.

Online program targets exercise, nutrition, brain training and mental health

Last year, a major international research collaboration on dementia prevention reported 14 modifiable risk factors that can reduce a person’s risk of developing dementia.

Participants in the new study had to have at least two of four risk factors — physical inactivity, cognitive inactivity, depression/anxiety and poor dietary habits — and were randomly assigned to either the intervention group or control group (which serves as a baseline for comparison).

Those in the intervention group were provided with personalised online coaching in two or more health modules according to their risk factors, while those in the control group were given module-related information only (e.g. the Australian Physical Activity Guidelines).

The intervention modules included:

• Physical activity: participants were advised to do 300 minutes of moderate intensity exercise or 150 minutes of vigorous intensity exercise per week as well as two days of moderate-vigorous intensity strength training per week, and daily balance training.
• Nutrition: participants were advised to follow a Mediterranean diet by consuming unprocessed plant foods including vegetables, fruits, legumes, grains, nuts/seeds and extra virgin olive oil, moderate amounts of fish and shellfish, and eating low amounts of meat, dairy, eggs and animal fats.
• Brain training: this training targeted seven cognitive domains (verbal executive, verbal memory, visual executive, visual memory, visual attention, speed and working memory) and allocated three 45-minute sessions each week across the first 10 weeks and then monthly sessions.
• Peace of mind: participants received training via ThisWayUp, a digital mental health program based on the principles of cognitive behavioural therapy aimed at reducing or preventing depression and anxiety.

Professor Brodaty said the online coaching was personalised “according to information [participants] had given us in questionnaires”.

“With nutrition, for example, they were given recipes, videos they could watch, and they were able to see how they were improving.”

In addition to improvements in cognitive scores, the researchers found self-reported improvements in aerobic activity, strength training, diet and depression scores.

“It’s not just cognition we’re benefiting,” Professor Brodaty said. “If people are exercising more and eating healthy, it’s better for their blood pressure, their weight, their heart.”

He added that the more people engaged with the trial, the better their results.

“A third of people [in the intervention group] did nothing, a third of people did something, and a third of people did a lot.

“As you’d expect, the people who did more did better than the people who did some, who did better than the people who did none.”

The study included participants from metropolitan, rural and remote areas.

“That’s one of the big advantages of doing it online … it has the potential to reach people wherever they live, to be accessible to anyone,” Professor Brodaty said.

Study builds on growing body of evidence

Ralph Martins, a professor of ageing and Alzheimer’s disease at Edith Cowan University (ECU), said the study was an important piece of research that provided “a lot of hope” that lifestyle interventions could play a key role in maintaining cognitive health.

“It’s a population-based study which is one of its major strengths, and the large number of participants is also pretty remarkable,” Professor Martins, director of the centre of excellence for Alzheimer’s disease research and care at ECU, said.

The research builds on a similar study first conducted in Finland (now being replicated in other countries, including Australia), which showed it was possible to prevent cognitive decline using “multi-domain lifestyle interventions” among older at-risk people.

“[The Maintain Your Brain study] uses an online approach, and that’s what makes it attractive,” Professor Martins said.

He noted, however, that it had some limitations, including reduced participation rates in the intervention group, with a third of participants not completing any tasks.

“The question is: is there a bias of self-selection of people who are more educated, more physically active? And are we missing out on people who are at the greatest risk [of dementia]?”

He added the study would have benefited from screening participants for certain genes that can increase a person’s risk of developing Alzheimer’s disease to determine how lifestyle interventions might benefit high-risk individuals.

‘Slip, slop, slap’ of brain health

Professor Brodaty said future research and implementation efforts should focus on targeting people with less education and from lower socioeconomic backgrounds, and be expanded to address more risk factors.

“We know high blood pressure is a risk factor, for example,” he said. “We did counsel people about this, but if we were to do it again, we’d like to work closely with primary health networks to enable GPs to use this as a prevention program.”

In the meantime, Professor Brodaty said the intervention could be scaled up and rolled out to a much wider population.

“Because [dementia] is a disease of late life, even delaying it by one year would reduce the numbers of people with it by 10 per cent.

“Australia-wide, there’s about 420 million people [with dementia]. So 42,000 people less would certainly be worthwhile.”

He said many people didn’t realise there were things they could do to delay cognitive decline, and eventually dementia — a disease “we all fear more than any other”.

“We think [lifestyle modifications] should be the ‘slip, slop, slap’ of brain health,” he said.

“We need to make [dementia prevention] a whole-of-health approach, because it would benefit not just the brain, but other parts of the body as well.”